During his six years as intelligence chief, Mr Maassen has earned the ire of Germany’s centre-left as an arch-conservative whose views had, of late, veered too much into far-right territory.

Political line

For them, he crossed a political line earlier this month for casting doubt on claims that a stabbing in eastern Germany had sparked vigilante attacks on immigrants.

After days of protest Mr Maassen relativised his doubts, claiming he had been misunderstood, but his comments echoed the far-right Alternative für Deutschland (AfD) and contradicted Dr Merkel’s own condemnation of the attacks.

After two weeks of messy Maassen headlines, the chancellor hoped she had arrived at a Solomonic solution on Tuesday: appease the SPD by moving Mr Maassen out of intelligence and into the interior ministry, as a deputy head.

But senior SPD party figures have dismissed the compromise as a “farce”. Party members flooded their Bundestag offices with complaints that a man they wanted fired is instead in a new job with more money, apparently with the SPD’s blessing.

On Wednesday, heading to an EU meeting in Austria, Dr Merkel left behind a fourth-term administration struggling to find its rhythm and exposed once again as riven with mistrust.

Before the summer break, the coalition came to the brink over hardline migration threats of Bavaria’s Christian Social Union (CSU), sister party to Dr Merkel’s CDU. That row has coloured this one, given CSU leader Horst Seehofer is federal interior minister in Berlin and boss of Mr Maassen.

On Wednesday the interior minister insisted he had not wanted to move Mr Maassen, whom he called a “man of integrity”, but that he was happy with the compromise.

Not so the SPD’s left-wing. They are demanding their six ministers block his appointment at cabinet. And, after weeks gunning for the deposed intelligence chief, they have redirected their fire at their own party leader.

Dr Merkel’s authority is faring little better. “All the world can see this government chief is seriously weakened,” said the Süddeutsche Zeitung daily, “without even the energy to spare her coalition serious crises from relatively minor cause.”